PTH 23 Bridge Rehabilitation Design

Originally constructed in 1968, the PTH 23 nine-span bridge had elements that were approaching the end of their design service life. As a crucial link between communities across the Red River—and a primary evacuation route for the town of Morris during flood events—the bridge needed to be updated to modern standards. Plus, seeding and harvesting timing consideration meant careful construction staging would be needed.

We performed a site inspection to confirm condition and identify constraint-induced fracture details. Precast deck panels were made composite with the steel girders by using ultra-high performance concrete grouted shear pockets and transverse joints. This was the Manitoba Department of Infrastructure’s first application of full width, full depth precast panels of this magnitude and complexity.

Our design incorporated structural health monitoring, which involved the installation of sensors that would monitor the continuity and composite action with the girders in the negative moment regions. To top it off, we used bridge weigh-in-motion technology that included the installation of sensors in two sections of a simply supported span. Their task was to collect data such as truck speed, axle spacing, and gross vehicle weight.

The rehabilitated bridge will continue to be a vital link for the community it serves, ensuring people are kept safe during floods.